The present disclosure broadly relates to the art of gas spring devices.
Gas spring devices of the subject disclosure find particular application and use in conjunction with suspension systems of wheeled vehicles, and will be described herein with specific reference thereto. However, gas spring devices of the present disclosure are also amenable to use in other applications and environments. Thus, it is to be understood that the specific uses shown and described herein are merely exemplary.
It is well known that land vehicles of most types and kinds are outfitted with a suspension system that supports a sprung mass (e.g., a body or chassis) of the vehicle on an unsprung mass (e.g., axles or wheel-engaging members) of the vehicle. It is also well known for some suspension systems to include gas spring devices that are operatively connected between the sprung and unsprung masses of the vehicle. Typically, such gas spring devices include two relatively rigid end members that are sealingly connected to respective open ends of a spring wall to at least partially form a spring chamber therebetween. The end members of such gas spring assemblies are often constructed of metal. However, in some constructions a substantially rigid plastic material has been used.
The spring wall of a conventional gas spring device is adapted to flex during dynamic operation and use of the gas spring device and is therefore normally made from a flexible, elastomeric material. During operation, the gas spring device is loaded such that opposing forces act against the end members. It is well recognized in the art that the spring wall does not itself support the load. Rather, the pressurized gas retained within the gas spring device by the spring wall acts against the end members and thereby provides forces capable of supporting loads applied to the end members.
To withstand the forces applied thereto by the aforementioned pressurized gas, existing spring walls generally include internal and/or external reinforcement in the form of additional materials and/or structures. Such internal and/or external reinforcement acts to buttress the elastomeric material of the spring wall and thereby help to restrict the expansion of the same, both under internal design pressures and under dynamic pressure levels associated with use under load. For example, some known wall constructions include internal structures in the form of reinforcement filaments or cords that are embedded in the material from which the spring wall is constructed. Other known spring wall constructions are used in association with external structures, such as a coil spring or a restraining cylinder, for example, that is disposed about at least a portion of the outer surface of the spring wall.
Notwithstanding the success and common usage of conventional gas spring constructions, certain areas of improvement in the art of gas spring devices still remain. One such area involves the reduction of manufacturing costs associated with the production of known spring walls. Typically, the manufacture of internally-reinforced spring walls involves a multitude of fabrication steps and processes that undesirably increase costs associated with the production thereof. Conversely, spring walls that utilize only external reinforcement are often less costly to manufacture. However, the costs associated with the attendant external reinforcement components (e.g., manufacturing, inventory and/or assembly costs) typically more than offset any cost savings associated with the flexible spring wall. What's more, the use of external reinforcement components and/or structures often raises other undesirable issues, such as increased wear and/or heat retention, for example. Furthermore, only a limited number of applications and/or environments are suitable for the use of such external reinforcement components.
Accordingly, it is believed desirable to develop unreinforced elastomeric spring walls for use in forming gas spring assemblies that overcome the foregoing and other disadvantageous qualities and/or characteristics associated with internally or externally reinforced spring walls.